Dental engine



(No Model.)

W. W. WILLIAMSON.

DENTAL ENGINE Patented Apr. 12, 1892.

WITNESSES:

IN ENTORI %M -u/ QIATTORNEYS ATENT @FFICE.

WVALLACE W. WILLIAMSON, OF SYBACUSE, NEW YORK.

DENTAL ENGINE.

SPECIFICATION forming part of Letters Patent No. 472,776, dated April 12, 1892.

Application filed May 28, 1891 Serial No. 394,425- (No model.)

To all whom it may concern.-

Be it known that LWALLAOE W.WILLIAM- -SON, of Syracuse, in the county of Onondaga,

by which I obtain an instrument which is better balanced, more eflicient and convenient in its operation, and simpler and cheaper in its manufacture.

The invention is fully illustrated in the annexed drawings, in which Figure 1 is a front elevation of an instrument embodying my invention. Fig. 2 is a transverse section of the same, taken on line a: at, Fig. 1. Fig. 3 is a transverse section on line y y, Fig. 2; and Fig. i is an enlarged detached side view of the shaft-coupling.

Similar letters of reference indicate corresponding parts.

B represents the driving-belt, which runs on pulleys p p,secured to the ceiling or other suitable support above the instrument to be operated by said belt, from which pulleys the belt is suspended in the form of a loop. Upon this loop of the belt rides the pulley P, which is rigidly secured to a shaft a, journaled in the case 0. This case completely surrounds the pulley P, so as to not only protect the same,but also the operator, from coming in contact therewith. I preferably make the said case of the form of a hollow spherical shell, which incloses and houses the pulley, together with its shaft and couplings and bearings of said shaft, and thus shields the same from dust, and when of this form I construct it of two hemispherical shells united at their peripheral edges by screw-threading the exterior of one and the interior of the other shell and screwing them together, as shown at 0. Said shells are provided, re-

spectively, with the tubular hubs c and c in their centers. The hub c is formed separate from the case and with an externally-screwthreaded portion on one end, by which it is screwed part way into an eye in the shell 0, leaving an enlarged smooth journal-bearing c at the inner end of the hub. The hub c of the other shell is preferably formed integral therewith and projects inwardly therefrom. The inner end of the interior of this hub is smooth to serve as a journal-bearing for one end of the shaft a, which extends diametrically across the interior of the case 0 and has its opposite end journaled in the bearing 0". One of the aforesaid shells is provided with guide openings or tubes 25 25, through which the belt B passes, and the interior of the shells is provided with guards b b to maintain the belt on the pulley P.

D represents the usual flexible shaft, to one end of which is attached the dental tool D. To the opposite end of the usual sheath of said shaft is secured the ferrule e, which is provided with the screw-threaded end portion 6' by which it is connected to the correspondingly screw-threaded outer end portion of the interior of the hub c. TheshaftD is detachably connected to the end of the shaft a, which latter is formed with the socket t', which terminates with a flat bearing j at its inner end, and the shaft D is inserted in said socket and terminates with a flat end portion f, which is seated on the bearing j, and thus the shaft D is compelled to rotate with the shaft a.

In order to counterbalance the side of the case with the shaft D attached thereto, I weight the opposite side of the case, preferably by forming the shell which constitutes the latter side of the case thicker to preponderate the other shell of the case.

In the hub c is journaled a shaft 1, which is connected at its inner end to the end of the shaft or inv the same manner as the shaft D, hereinbefore described. To the outer end of the shaft Z I attach a fan F, which is thus rotated simultaneously with the operation of the shaft D and serves to blow air, toward the face of the person operated on by the dentist using the instrument attached to the shaft D.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In combination with the suspended driving-belt and pulley riding on said belt and carried thereby,a protecting-case completely surrounding said pulley and provided with guide-openings receiving through them the aforesaid belt and a shaft fixed to the pulley and journaled in the case and extending through the latter for transmitting motion by its outer end, as setforth.

2. In combination with a suspended driving-belt and pulley riding thereon, a case inclosing said pulley and provided with guideopenings receiving through them the aforesaid belt, a shaft fixed to thepulley and journaled to opposite sides of the case and extending, through the side thereof for transmitting motion by its outer end, and aconnterpoise on the case at the opposite end of the pulley-shaft, substantially as and for the purpose set forth.

3. In combination with the suspended driving-belt and pulley ridingon said belt, a case inclosing and housing said pulley and provided with openings for the passage he belt, a shaft affixed to the pulley and journaled in the sides of the case, a shaft at the exterior of the case, connected to one end of the pulley-shaft, and a counterpoise formed on the interior of the case at the opposite end of the pulley-shaft, as set forth and shown.

4. In combination with the suspended driving-belt and pulley riding thereon, a case inclosing said pulley and composed of two concaveshells detachably united at their peripheral edges, each of said shells being formed with a j ournal-bearin g extending through the center of the shell and one of said shells having passages through it for the belt, a shaft extending diametrically through the case and its journal-bearings and having the aforesaid pulley secured to it, and a shaft at the exterior of the ease, secured to the incased shaft, as set forth.

5. In combination with the suspended driving-belt B and pulley P riding thereon, the case 0, composed of two hemispherical shells detachably united at their peripheral edges and each provided with a journal-bearing extending through the center of the shell and one of said shells being weighted to preponderate the companion shell, the shaft a, extending through the case and journaled in the aforesaid bearings and having the pulley P secured to mend guardsb b on the interior of the case to maintain the belt on the pulley, as setforth andshown. V

' 6. In combination with the case 0, provided with the tubular hubs c c; the shaft a, journaled in'said hubs and confirmed from longitudinal movement and formed with the socket z, terminating with the flat bearing jat' the inner end of the socket, and a shaft inserted in said socket and terminating with the flat end portion f, seated .on the fiat bearing substantially as'described and shown.

'In testimony whereof Ihave hereunto signed my name this 25th day of May, 1891. I

- WALLACE W. WILLIAMSON. [u 8.] Witnesses: H. M. SEAMA s, J. J J LAAs's. 

